CUSIP No. 942749 10 2                 13G                         Page 1 of 17


                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                 ---------------

                                  SCHEDULE 13G
                                 (Rule 13d-102)

             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
          TO RULES 13d-1(b), (c), AND (d) AND AMENDMENTS THERETO FILED
                              PURSUANT TO 13d-2(b)
                               (Amendment No. 19)*


                         WATTS WATER TECHNOLOGIES, INC.
                         ------------------------------
                                (Name of Issuer)

                 Class A Common Stock, par value $.10 per share
                 ----------------------------------------------
                         (Title of Class of Securities)

                                   942749 10 2
                                   -----------
                                 (CUSIP Number)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

      |_| Rule 13d-1(b)
      |_| Rule 13d-1(c)
      |X| Rule 13d-1(d)

--------------------------------------------------------------------------------

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act.


CUSIP No. 942749 10 2                 13G                         Page 2 of 17


--------------------------------------------------------------------------------
1.    Name of Reporting Person
      I.R.S. Identification No. of Above Persons (Entities Only)

      Timothy P. Horne
--------------------------------------------------------------------------------
2.    Check the Appropriate Box if a Member of a Group      (a) |X|
                                                            (b) |_|

--------------------------------------------------------------------------------
3.    SEC Use Only


--------------------------------------------------------------------------------
4.    Citizenship or Place of Organization

      United States
--------------------------------------------------------------------------------
              5.    Sole Voting Power
  Number of         7,286,574
   Shares     ------------------------------------------------------------------
Beneficially  6.    Shared Voting Power
  Owned by          50,000
    Each      ------------------------------------------------------------------
  Reporting   7.    Sole Dispositive Power
   Person           1,697,114
    With      ------------------------------------------------------------------
              8.    Shared Dispositive Power
                    4,404,680
--------------------------------------------------------------------------------
9.    Aggregate Amount Beneficially Owned by Each Reporting Person

      7,336,574
--------------------------------------------------------------------------------
10.   Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares   |_|


--------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row 9

      22.7%
--------------------------------------------------------------------------------
12.   Type of Reporting Person

      IN
--------------------------------------------------------------------------------


CUSIP No. 942749 10 2                 13G                         Page 3 of 17


--------------------------------------------------------------------------------
1.    Name of Reporting Person
      I.R.S. Identification No. of Above Persons (Entities Only)

      George B. Horne
--------------------------------------------------------------------------------
2.    Check the Appropriate Box if a Member of a Group      (a) |X|
                                                            (b) |_|

--------------------------------------------------------------------------------
3.    SEC Use Only


--------------------------------------------------------------------------------
4.    Citizenship or Place of Organization

      United States
--------------------------------------------------------------------------------
              5.    Sole Voting Power
  Number of         None
   Shares     ------------------------------------------------------------------
Beneficially  6.    Shared Voting Power
  Owned by          50,000
    Each      ------------------------------------------------------------------
  Reporting   7.    Sole Dispositive Power
   Person           None
    With      ------------------------------------------------------------------
              8.    Shared Dispositive Power
                    1,974,600
--------------------------------------------------------------------------------
9.    Aggregate Amount Beneficially Owned by Each Reporting Person

      1,974,600
--------------------------------------------------------------------------------
10.   Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares  |_|


--------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row 9

      7.3%
--------------------------------------------------------------------------------
12.   Type of Reporting Person

      IN
--------------------------------------------------------------------------------


CUSIP No. 942749 10 2                 13G                         Page 4 of 17


                            STATEMENT ON SCHEDULE 13G

Item 1(a). Name of Issuer.*

               Watts Water Technologies, Inc.

Item 1(b). Address of Issuer's Principal Executive Offices.

               815 Chestnut Street
               North Andover, MA  01845

Item 2(a). Names of Persons Filing.

               Timothy P. Horne
               George B. Horne


Item 2(b). Address of Principal Business Office or, if None, Residence.

               c/o Watts Water Technologies, Inc.
               815 Chestnut Street
               North Andover, MA  01845

Item 2(c). Citizenship.

               United States

Item 2(d). Title of Class of Securities.

               Class A Common Stock, par value $.10 per share

--------------------
*     Unless otherwise indicated, information contained in an Item pertains to
      all members of the group making this filing.


CUSIP No. 942749 10 2                 13G                         Page 5 of 17


Item 2(e). CUSIP Number.

            942749 10 2

Item 3. If This Statement is Filed Pursuant to Rule 13d-1(b), or 13d-2(b) or
(c), Check Whether the Person Filing is a:

(a)   |_| Broker or dealer registered under Section 15 of the Exchange Act.

(b)   |_| Bank as defined in Section 3(a)(6) of the Exchange Act.

(c)   |_| Insurance company as defined in Section 3(a)(19) of the Exchange Act.

(d)   |_| Investment company registered under Section 8 of the Investment
          Company Act.

(e)   |_| An investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E);

(f)   |_| An employee benefit plan or endowment fund in accordance with Rule
          13d-1(b)(1)(ii)(F);

(g)   |_| A parent holding company or control person in accordance with Rule
          13d-1(b)(1)(ii)(G);

(h)   |_| A savings association as defined in Section 3(b) of the Federal
          Deposit Insurance Act;

(i)   |_| A church plan that is excluded from the definition of an investment
          company under Section 3(c)(14) of the Investment Company Act;

(j)   |_| Group, in accordance with Rule 13d-1(b)(1)(ii)(J).

      Not Applicable.


CUSIP No. 942749 10 2                 13G                         Page 6 of 17


Item 4. Ownership.

      Timothy P. Horne

      (a) Amount Beneficially Owned:

         Timothy P. Horne (for purposes of this particular Item 4, "Mr. Horne")
         is deemed the beneficial owner of 7,336,574 shares of Class A Common
         Stock of the Issuer. As noted below, a substantial portion of Mr.
         Horne's beneficial ownership of Class A Common Stock is derived from
         beneficial ownership of Class B Common Stock, par value $.10 per share,
         of the Issuer which is convertible into Class A Common Stock on a
         share-for-share basis.

         Includes (i) 1,651,220 shares of Class B Common Stock held by Mr.
         Horne, (ii) 1,210,840 shares of Class B Common Stock and 4,200 shares
         of Class A Common Stock held by a revocable trust for the benefit of
         Daniel W. Horne, Mr. Horne's brother, for which Mr. Horne serves as
         sole trustee, (iii) 1,210,840 shares of Class B Common Stock and 4,200
         shares of Class A Common Stock held by a revocable trust for the
         benefit of Deborah Horne, Mr. Horne's sister, for which Mr. Horne
         serves as sole trustee, which trust is revocable with the consent of
         the trustee, (iv) 1,085,840 shares of Class B Common Stock held by a
         revocable trust for the benefit of Peter W. Horne, Mr. Horne's brother,
         for which Peter W. Horne serves as sole trustee, (v) 1,924,600 shares
         of Class B Common Stock and 50,000 shares of Class A Common Stock held
         for the benefit of George B. Horne, Mr. Horne's father, under a
         revocable trust for which Mr. Horne and George B. Horne serve as
         co-trustees, (vi) 22,600 and 20,200 shares of Class B Common Stock held
         for the benefit of Tiffany Rae Horne (Mr. Horne's daughter) and Tara V.
         Horne (Mr. Horne's daughter), respectively, under irrevocable trusts
         for which Mr. Horne serves as trustee, (vii) 3,094 shares of Class A
         Common Stock issuable upon the exercise of stock options within 60 days
         of December 31, 2004, and (viii) 1,200 shares of Class A Common Stock
         issued to Mr. Horne as a restricted stock award under the Watts Water
         Technologies, Inc. 2004 Stock Incentive Plan, which remain subject to
         certain restrictions on the transfer or disposition of such shares. All
         of the shares of Class B Common Stock noted in clause (i), all of the
         shares of Class B Common Stock noted in clause (ii), all of the shares
         of Class B Common Stock noted in clause (iii), all of the shares of
         Class B Common Stock noted in clause (iv), all of the shares of Class B
         Common Stock noted in clause (v), and all of the shares of Class B
         Common Stock noted in clause (vi) (7,273,880 shares of Class B Common
         Stock in the aggregate) are subject to The Amended and Restated George
         B. Horne Voting Trust Agreement - 1997 ("1997 Voting Trust") for which
         Mr. Horne serves as trustee. (See Exhibit 4 for a description of the
         1997 Voting Trust).


CUSIP No. 942749 10 2                 13G                         Page 7 of 17


      (b) Percent of Class:

            (See Exhibit 1)

      (c) Number of shares as to which such person has:


            (i)   sole power to vote or to direct the vote

                  7,286,574

            (ii)  shared power to vote or to direct the vote

                  50,000

            (iii) sole power to dispose or to direct the disposition of

                  1,697,114

            (iv)  shared power to dispose or to direct the disposition of

                  4,404,680


CUSIP No. 942749 10 2                 13G                         Page 8 of 17


Item 4. Ownership.

      George B. Horne

      (a) Amount Beneficially Owned:

         George B. Horne (for purposes of this particular Item 4, "Mr. Horne")
         is deemed the beneficial owner of 1,974,600 shares of Class A Common
         Stock of the Issuer. As noted below, a substantial portion of Mr.
         Horne's beneficial ownership of Class A Common Stock is derived from
         beneficial ownership of Class B Common Stock, par value $.10 per share,
         of the Issuer which is convertible into Class A Common Stock on a
         share-for-share basis.

         Mr. Horne's beneficial ownership consists of 1,924,600 shares of Class
         B Common Stock and 50,000 shares of Class A Common Stock held in a
         revocable trust for which Timothy P. Horne and George B. Horne serve as
         co-trustees. All of such shares of Class B Common Stock are subject to
         the 1997 Voting Trust for which Timothy P. Horne serves as sole
         trustee. (See Exhibit 4 for a description of the 1997 Voting Trust).

      (b) Percent of Class:

            (See Exhibit 1)

      (c) Number of shares to which such person has:

            (i)   sole power to vote or to direct the vote

                  None

            (ii)  shared power to vote or to direct the vote

                  50,000

            (iii) sole power to dispose or to direct the disposition of

                  None

            (iv)  shared power to dispose or to direct the disposition of

                  1,974,600


CUSIP No. 942749 10 2                 13G                         Page 9 of 17


Item 5. Ownership of Five Percent or Less of a Class.

      Not Applicable

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

      Timothy P. Horne

         George B. Horne has the right to receive and the power to direct the
         receipt of dividends from, or the proceeds from the sale of, 1,924,600
         shares of Class B Common Stock and 50,000 shares of Class A Common
         Stock held for the benefit of George B. Horne under a revocable trust
         for which Timothy P. Horne and George B. Horne serve as co-trustees.

         Daniel W. Horne has the right to receive and the power to direct the
         receipt of dividends from, or the proceeds from the sale of, 1,210,840
         shares of Class B Common Stock and 4,200 shares of Class A Common Stock
         held for the benefit of Daniel W. Horne under a revocable trust for
         which Timothy P. Horne serves as sole trustee.

         Deborah Horne has (subject to obtaining the consent of the trustee as
         described below) the right to receive and the power to direct the
         receipt of dividends from, or the proceeds from the sale of, 1,210,840
         shares of Class B Common Stock and 4,200 shares of Class A Common Stock
         held for the benefit of Deborah Horne under a trust for which Timothy
         P. Horne serves as sole trustee, which trust is revocable with the
         consent of the trustee.

         Peter W. Horne has the right to receive and the power to direct the
         receipt of dividends from, or the proceeds from the sale of, 1,135,840
         shares of Class B Common Stock held for the benefit of Peter W. Horne
         under a revocable trust for which Peter W. Horne serves as sole
         trustee.

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

      George B. Horne

         Timothy P. Horne shares the power, as co-trustee with George B. Horne
         of a revocable trust for the benefit of George B. Horne and subject to
         the limitations of such trust, to direct the receipt of dividends from,
         or the proceeds from the sale of, 1,924,600 shares of Class B Common
         Stock and 50,000 shares of Class A Common Stock held in such trust.



CUSIP No. 942749 10 2                 13G                         Page 10 of 17


Item 7. Identification and Classification of the Subsidiary which Acquired the
Security Being Reported on by the Parent Holding Company.

         Not Applicable

Item 8. Identification and Classification of members of the Group.

         A group has filed this Schedule 13G pursuant to Rule 13d-1(c). See
         Exhibit 3 for the identity of each member of the group.

Item 9. Notice of Dissolution of Group.

      Not Applicable

Item 10. Certification.

      Not Applicable


CUSIP No. 942749 10 2                 13G                         Page 11 of 17


                                   SIGNATURES

      After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

Dated:  February 8, 2005


      /s/ Timothy P. Horne
      ------------------------
      TIMOTHY P. HORNE

      /s/ Kenneth J. McAvoy*
      ------------------------
      GEORGE B. HORNE



*     By Kenneth J. McAvoy, Attorney in Fact pursuant to Powers of Attorney
      filed with the Securities and Exchange Commission on February 12, 1992,
      which Powers of Attorney are hereby incorporated herein by reference.


CUSIP No. 942749 10 2                 13G                         Page 12 of 17


                                INDEX OF EXHIBITS

1.    Voting Percentages

2.    Amended and Restated Stock Restriction Agreement

3.    Identity of Group Members

4.    The Amended and Restated George B. Horne Voting Trust Agreement - 1997


CUSIP No. 942749 10 2                 13G                         Page 13 of 17


                                    EXHIBIT 1


      The following table indicates total percentage of voting power of
outstanding shares of the Issuer possessed by any group member who has sole or
shared voting power of any shares and by the group as a whole. Due to the fact
that each share of Class A Common Stock is entitled to one vote on all matters
submitted to stockholders and each share of Class B Common Stock is entitled to
ten votes on all such matters, equity percentage is not equivalent to voting
percentage.

                  Stockholder             Voting Percentage
                  -----------             -----------------

                  Timothy P. Horne              73.9%
                  George B. Horne                0.1%
                  -----------------------------------

                  Group                         73.9%

      The following table indicates the percentage of the outstanding shares of
Class A Common Stock beneficially owned by each group member and by the entire
group as a whole. The percentages were determined in accordance with Rule 13d-3
under the Securities Exchange Act of 1934, as amended.

                  Stockholder             Equity Percentage
                  -----------             -----------------

                  Timothy P. Horne              22.7%
                  George B. Horne                7.3%
                  -----------------------------------

                  Group                         22.7%


CUSIP No. 942749 10 2                 13G                         Page 14 of 17


                                    EXHIBIT 2


      All Class B Common Stock shares beneficially owned by members of the group
are held individually by or in trust for the benefit of Timothy P. Horne, George
B. Horne, Daniel W. Horne, Deborah Horne, Tara V. Horne, Tiffany R. Horne and
Peter W. Horne, and any voting trust certificates representing such shares, are
subject to an Amended and Restated Stock Restriction Agreement (the
"Agreement"). Upon any proposed voluntary transfer or transfer by operation of
law of Class B Common Stock or voting trust certificates representing such
shares by any of the above stockholders, or upon the death of such a stockholder
holding such shares or voting trust certificates, the other parties to the
Agreement (other than George B. Horne) have a pro rata right of first refusal to
purchase such shares (including a second opportunity to elect to purchase any
shares not purchased under the first right of refusal).

      The purchase price per share is the 15-day average trading price of the
Issuer's Class A Common Stock while publicly traded, except in the case of
certain involuntary transfers, in which case the purchase price is book value.

      This summary is qualified in its entirety by reference to the text of the
Agreement which is incorporated herein by reference to Exhibit 2 to the Issuer's
Current Report on Form 8-K dated October 31, 1991, and to the text of Amendment
No. 1 to the Agreement which is incorporated herein by reference to Exhibit
10.21 to the Issuer's Annual Report on Form 10-K dated September 16, 1997.


CUSIP No. 942749 10 2                 13G                         Page 15 of 17


                                    EXHIBIT 3


Item 8 Continued.

      The members of the group are:

      Timothy P. Horne
      George B. Horne


CUSIP No. 942749 10 2                 13G                         Page 16 of 17


                                    EXHIBIT 4

      The 1,651,220 shares of Class B Common Stock held by Timothy P. Horne,
individually, 1,210,840 shares of Class B Common Stock held by a trust for the
benefit of Daniel W. Horne, 1,210,840 shares of Class B Common Stock held by a
trust for the benefit of Deborah Horne, 1,924,600 shares of Class B Common Stock
held by a trust for the benefit of George B. Horne, 1,085,840 shares of Class B
Common Stock held by a trust for the benefit of Peter W. Horne, and 22,600 and
20,200 shares of Class B Common Stock held for the benefit of Tiffany Rae Horne
(Mr. Horne's daughter) and Tara V. Horne (Mr. Horne's daughter), respectively,
under irrevocable trusts for which Mr. Horne serves as trustee, (7,273,880
shares of Class B Common Stock in the aggregate) are subject to the terms of The
George B. Horne Voting Trust Agreement-1997 (the "1997 Voting Trust"). Under the
terms of the 1997 Voting Trust, the trustee (currently Timothy P. Horne) has
sole power to vote all shares subject to the 1997 Voting Trust.

      Under the terms of the 1997 Voting Trust, in the event Timothy P. Horne
ceases to serve as trustee of the 1997 Voting Trust, then David Dietz, whose
professional corporation is a partner in the law firm of Goodwin Procter LLP,
and Walter J. Flowers, a partner in the law firm of Flowers and Manning, LLP
(each, a "Successor Trustee" and collectively, the "Successor Trustees"), shall
thereupon become co-trustees of the 1997 Voting Trust if such individuals are
willing and able to succeed. At any time, Timothy P. Horne, if then living and
not subject to incapacity, may designate up to two additional persons, one to be
designated as the primary designee (the "Primary Designee") and the other as the
secondary designee ("Secondary Designee"), to serve in the stead of any
Successor Trustee who shall be unable or unwilling to serve as a trustee of the
1997 Voting Trust. Such designations are revocable by Timothy P. Horne at any
time prior to the time at which such designees become a trustee. If any of the
Successor Trustees is unable or unwilling or shall otherwise fail to serve as a
trustee of the 1997 Voting Trust, or after becoming a co-trustee shall cease to
serve as such for any reason, then a third person shall become a co-trustee with
the remaining two trustees, in accordance with the following line of succession:
first, any individual designated as the Primary Designee, next, any individual
designated as the Secondary Designee, and then, an individual appointed by the
holders of a majority in interest of the voting trust certificates then
outstanding. In the event that the Successor Trustees shall not concur on
matters not specifically contemplated by the terms of the 1997 Voting Trust, the
vote of a majority of the Successor Trustees shall be determinative. No trustee
or Successor Trustee shall possess the Determination Power unless it is
specifically conferred upon such trustee pursuant to the provisions of the 1997
Voting Trust.

      The 1997 Voting Trust expires on August 26, 2021, subject to extension on
or after August 26, 2019 by stockholders (including the trustee of any trust
stockholder, whether or not such trust is then in existence) who deposited
shares of Class B Common Stock in the 1997 Voting Trust and are then living or,
in the case of shares in the 1997 Voting Trust the original depositor of which
(or the trustee of the original depositor of which) is not then living, the
holders of voting trust certificates representing such shares. The 1997 Voting
Trust may be amended by vote of the holders of a majority of the voting trust
certificates then outstanding and by the number of trustees authorized to take
action at the relevant time. Shares may not be removed from the 1997 Voting
Trust during its term without the consent of the trustees. The 1997 Voting Trust



CUSIP No. 942749 10 2                 13G                         Page 17 of 17


expires on August 26, 2021, subject to extension on or after August 26, 2019 by
stockholders (including the trustee of any trust stockholder, whether or nor
such trust is then in existence) who deposited shares of Class B Common Stock in
the 1997 Voting Trust and are then living or, in the case of shares in the 1997
Voting Trust the original depositor of which (or the trustee of the original
depositor of which) is not then living, the holders of voting trust certificates
representing such shares. The 1997 Voting Trust may be amended by vote of the
holders of a majority of the voting trust certificates then outstanding and by
the number of trustees authorized to take action at the relevant time. Shares
may not be removed from the 1997 Voting Trust during its term without the
consent of the trustees.

      This summary is qualified in its entirety by reference to the 1997 Voting
Trust which is incorporated herein by reference to Exhibit 9.2 of the Issuer's
Annual Report on Form 10-K dated September 28, 1999 filed with the Securities
and Exchange Commission.